Beyond Chemotherapy – Other Drugs Used to Treat Breast Cancer

Drugs Used to Treat Breast Cancer

There are several different drugs used to treat breast cancer. The first drugs people think about when they hear about cancer is chemotherapy drugs. While chemotherapy plays an important role in the treatment of breast cancer, it is not the only class of drugs that are used.[1],[2] The following are the most common classes of drugs, aside from chemotherapy, that are used to treat breast cancer[3]:

  • Hormonal therapy – The three types are estrogen receptor downregulators (ERDs), selective estrogen receptor modulators (SERMs) and aromatase inhibitors (AIs)[4]
  • Immunotherapy – This type of breast cancer treatment boosts or mimics the body’s own immune system to fight cancer
  • Targeted therapy – This category includes drugs that are also found in hormonal and immunotherapy classes. These drugs are designed to target one type of cell through one specific receptor or protein.[5]

Below is a chart that classifies each of these drugs, their purpose and side effects.[6],[7]

Name of Drug Characteristics Treatment Category Purpose Most Common Risks and Side Effects
Anastrozole Selective non steroidal  antineoplastic Aromatase inhibitor (AI) – hormonal therapy, targeted therapy Treats hormone receptor + post menopausal women for advanced or metastic breast cancer Headache, hot flashes, pain, nausea, back pain, asthenia
Bevacizumab (Avastin) Monoclonal antibody Immune therapy, targeted therapy Inhibits vascular endothelial growth factor (VEGF) dizziness, headache, hypertension, constipation, diarrhea, vomiting, dyspnea, dry skin
Estradiol Hormone therapy Palliative treatment for advance, inoperable breast cancer Vaginitis, chest pains, ovarian cancer
Esterified estrogen Estrogen Hormone therapy Palliative treatment for metastic breast cancer Endometrial hyperplasia
Etanidazole Hypoxic  radiosensitizers Given prior to radiation to increase the effectiveness of the therapy Hand- foot syndrome
Exemestane (Aromasin) SteroidalAntineoplastic AI hormonal therapy decrease estrogen production and suppresses growth of estrogen-dependent tumors Fatigue, nausea, hot flashes, nausea, lymphopenia, increased sweating
Fulvestrant (Faslodex)  Antineoplastic ERDs Estrogen receptor antagonist for ER+ breast cancer with progression after antiestrogen therapy Asthenia, hot flashes, headache, pain, nausea, vomiting, constipation, abdominal pain, diarrhea, back pain, injection site pain
Goserlin acetate (Zoladex) Gonadotropin releasing hormone analogue Hormone therapy Palliative treatment for women with advanced stages of breast cancer in both pre and peri menopausal women. Administered monthly Dizziness, insomnia, sexual dysfunction, heart failure
Imiquimod(Aldara) Immune response modifier Topical treatment boosts body’s own response to infection and disease Ulceration, skin irritation, fatigue headaches
Indomethacin Nonsteroidal anti inflammatory drug (NSAID) Powder, injection non-steroidal, anti-inflammatory drugs, reduce tumor induced suppression of the immune system, increases the effectiveness of other anti-cancer drugs Headache, pancreatitis, Stevens-Johnson syndrome, hyperkalemia
Lapatinib(Tykerb) Dual kinase inhibitor dual tyrosine kinase inhibitor Interrupts the HER-2 growth receptor pathway, suppressing cancer growth Diarrhea, palmar-plantar erythrodysesthesia, nausea, rash vomiting,  fatigue
 Letrozole Antineoplastic, Non steroidalGlucocorticoid AI Inhibits production of the aromatase enzyme and ultimately estrogen production in postmenopausal womenAdjuvant treatment for women with hormone receptor +breast cancer Hot flashes, nausea, bone pain, limb pain
Megestrol acetate progestin  Hormonal therapy Inhibits tumor growth by inhibiting pituitary and adrenal steroidogenesis Pulmonary embolism, heart failure, weight gain
Methotrexate Folic acid antagonist Combined with cyclophophamide and fluorouracil to combat severe cancer Acute toxicity, renal failure, nausea, vomiting, stomatitis
Pamidronate biphosphonate Hormonal drug Helps prevent bone loss secondary to estrogen blockade Hypertension, seizures, atrial fibrillation, abdominal pain, renal failure, vomiting, nausea, infusion site reaction, anemia
Raloxifene (Evista) SERM Hormonal therapy Postmenopausal treatment of breast cancer Sinusitis, athralgia, flulike syndrome, hot flashes
Tamoxifen AntineoplasticNonsteroidal antiestrogen SERMsHormonal therapy Inhibits estrogen’s cancer inducing activityAdjuvant treatment Stroke, nausea, vomiting, diarrhea, rash, fluid retention, hot flashes, vomiting, vaginal discharge, endometrial cancer
Testolactone (Teslac) Androgen For advanced cancer in postmenopausal women New breast lumps, vaginal bleeding, bone pain, anaphylaxis, nausea, vomiting, thirst
Thiotepa (Thioplex) DNA-Alkylater Adenocarcinoma of the breast Nausea, leucopenia, laryngeal edema, anaphylaxis, vomiting
Toremifen (Fareston) Nonsteroidal antiestrogen SERMHormone therapy Metastatic ER+ breast cancer in postmenopausal women Hot flashes, cataracts, nausea, sweating pulmonary embolism
Trastuzumab (Herceptin) Monoclonal antibody Immunotherapy Prevent recurrence in human epidermal growth factor receptor (HER-2) + breast cancer Dizziness, headaches, fever, insomnia, pain, heart failure, abdominal pain, anorexia, diarrhea, nausea, vomiting, increased cough, rash, acne, flulike syndrome, chills, dyspnea


These medicines are often used in combination with chemotherapy to treat breast cancer, improve your survival and prevent recurrence.


1 Romond, EH; Perez, EA; Bryant, J; Suman, VJ: Geyer, Jr., CE; Davidson, NE; Tan-Chiu, E; Martino, SM; Paik, SP; Kaufman, PA; Swain, SM; Pisansky, TM; Fehrenbacher, L; Kutteh, LA; Vogel, VG; Visscher, DW; Yothers, G; JenkinsRB; Brown, AM; Dakhil, SR; Mamounas, EP; Lingle, WL; Klein, PM; Ingle, JN; and Wolmark, N (2005). Trastuzumab Plus Adjuvant Chemotherapy for Operable HER2-Positive Breast Cancer. N England Journal of Medicine, 353:1673–1684; and ATAC The Arimidex, Tamoxifen, Alone or in Combination (ATAC) Trialists’ Group (2008).

2 “Effect of Anastrozole and Tamoxifen as Adjuvant Treatment for Early-Stage Breast Cancer: 100-Month Analysis of the Trial.” The Lancet Oncology, 9 (1): 45-53.

3 Ricks, D (2005). Breast Cancer Basics and Beyond. Alameda, CA: Hunter House, Inc.

4 Sarg, M. S. and Gross, A. D. (2007). The Cancer Dictionary Third Edition. New York: Checkmark Books.

5 Tripathy, D (2005). “Targeted Therapies in Breast Cancer.” The Breast Journal, 11(s1):S30–S35.

6 Nursing 2010 Drug Handbook (2010). New York: Lippincott, Williams and Williams.

7 Turkington, C; and Krag, K (2005). The Encycopedia of Breast Cancer. New York: FOF.

This article was originally published on July 27,2012 and last revision and update of it was 9/2/2015.